States of Matter

How do you describe a solid?

  • A solid has a definite shape and a definite volume
  • Key Idea: this fixed, closely packed arrangement of particles in a solid cause it to have a definite shape and volume.
  • Crystalline solids- solids that are made up of crystals are called
  • amorphous solids- the particles are not arranged in a regular pattern
  • liquid- has a definite volume but no shape of its own.
  • key idea- because its particles are free to move, a liquid has no definite shape. However, it does have a definite volume
  • Fluid- a liquid is also called a fluid, meaning a substance that flows
  • surface tension- is an inward force, or pull, among the molecules in a liquid that brings the molecules on the surface closer together.
  • Viscosity- a liquid’s resistance to flowing
  • gas- has neither a definite shape nor a definite volume
  • key idea- as gas particles move, they spread apart, filling all the space available. Thus, a gas has neither a definite shape nor a definite volume
  • pressure- of the gas is the force of its outward push divided by the area of the walls of the container

Chapter 2- changes in state

  • melting - change in state from a solid from a solid to a liquid

  • melting point- melting occurs at a specific temperature, called the melting point

  • key idea- at a solids melting point, its particles vibrate so fast that they break free from their fixed positions.

  • freezing- the change of state from a liquid to a solid

  • key idea- at a liquids freezing point, its particles are moving so slowly that they begin to take on fixed position

  • vaporization- the change in state from a liquid to a gas

  • key idea- vaporization occurs when the particles in a liquid gain enough

  • How are pressure and temperature of gas related?

    • key idea- when the temperature of a gas at constant volume is increased, the pressure of the gas increases. When the temperature is decreased, the pressure of the gas decreases.
    • charles’s law- when the temperature of a gas at constant pressure is increased, its volume increases. When the temperature of a gas at constant pressure is decreased, its volume decreases.
    • directly proportional- when the graph of two variables is said to be DP, to each other.

    Boyles law:

    • key idea- when the pressure of a gas at constant temperature is increased, the volume of the gas decreases. When the pressure is decreased, the volume increases.
    • Boyles law- this relationship between the pressure and the volume of the gas
    • inversely proportional- when the product of two variables is constant, the variables are IP to each other